Wolff had previously estimated that Ferrari's advantage on straights was worth as much as eight tenths of a second per lap.
However, that appeared to dissipate at COTA, with Charles Leclerc finishing over 50 seconds down on race-winner Bottas after Vettel had retired amid a woeful start to the race.
It was revealed before the race that Red Bull had proposed a fuel flow system to the FIA, which prompted the governing body to clarify that similar systems would be deemed illegal.
This was seen as an attempt by Red Bull to out the secrets of Ferrari's success and when the red cars' struggle was put to Max Verstappen, he told Ziggo Sport: "That's what happens when you stop cheating."
Although Wolff was unsure if the TD and Ferrari's lack of pace in the States was linked, he was clear that something had suddenly changed for Vettel and Leclerc.
"We just had a discussion about the data from the race, and the speed trace looks totally different to the last few races," Wolff said.
"Whether it's down to the technical directive or down to another issue, I honestly don't know as we can't look into what Ferrari has done.
"If someone was doing what the technical directive clarified, it would have been foul play.
"The way the technical directive was formulated, it was a severe breach of regulation, so there was not even any talk of grey areas."
Mattia Binotto and Leclerc both staunchly defended Ferrari after the race, insisting that the perceived struggles for pace had nothing to do with something fundamental changing on the SF90.
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